The present invention relates to an ultrasonic endoscope incorporating an ultrasonic vibrator in a hard distal end portion thereof.
In general, an ultrasonic endoscope is known which incorporates an ultrasonic vibrator for transmitting and receiving ultrasonic waves in a hard distal end portion of an insertion portion of the endoscope. The ultrasonic endoscope can obtain a tomographic image in the depth direction of, e.g., a body cavity wall by ultrasonic waves transmitted or received through the ultrasonic vibrator in the hard distal end portion. When the ultrasonic endoscope scans the ultrasonic waves using the ultrasonic vibrator in the hard distal end portion to obtain a tomographic image of the opposing wall, a better tomographic image with less attenuation can be obtained if the ultrasonic waves are scanned not through an air gap but through a liquid.
For this reason, various conventional ultrasonic endoscopes have been developed, and the typical one is disclosed in Japanese Patent Disclosure (Kokai) No. 58-65148.
As shown in FIGS. 1 and 2, conventional ultrasonic endoscope a disclosed in Japanese Patent Disclosure (Kokai) No. 58-65148 has manipulating portion f used by an operator such as a doctor, and insertion portion g extending from manipulating portion f and inserted in a body cavity. Hard portion b is coupled to the distal end of insertion portion b through soft portion k and bent portion l. Ultrasonic vibrator c is mounted on the outer surface of hard portion b, and an observation optical system is mounted on the distal end face thereof. Ultrasonic vibrator c mounted on the outer surface of hard distal end portion b is covered with balloon d, two ends of which are fixed.
A water-supply path for supplying washing water for washing the observation optical system and water injection path e for injecting water into balloon d extend in insertion portion g of endoscope a therealong. After water is injected into balloon d through path e, ultrasonic waves are scanned to the opposing wall through the water in balloon d.
Endoscope connector n and electrical connector p are mounted on distal ends of universal cord m and signal cable o connected to manipulating portion f, respectively. Connector n is coupled to an ultrasonic wave observation apparatus, and connector n is connected to a light source. Connector p is coupled, through an appropriate tube, to a water-supply tank arranged in a separate location, and water is supplied to the watersupply path for the washing water of the observation optical system.
Sub-manipulating portion h is coupled between manipulating portion f and insertion portion g. Portion h is provided with liquid supply port i and suction manipulation valve j. Upon operation of vibrator c, a liquid supply syringe is coupled to port i of portion h, and water is injected from the syringe into balloon d sequentially through port i and path e. Note that reference symbol q denotes a balloon suction hole; and r, a suction port formed in endoscope connector n.
In the conventional ultrasonic endoscope, the water-supply syringe must be coupled to liquid-supply port i of sub-manipulating portion h upon operation of ultrasonic vibrator c, and water must be injected from the syringe into balloon d sequentially through port i and path e. Therefore, during the use of endoscope a, the syringe must be mounted on port i of portion h, and must be manually operated, resulting in cumbersome operation and poor operability.
Another arrangement can be considered wherein a liquid supply pipe coupled to an automatic liquid supply pump is coupled to liquid supply port i of submanipulating portion h, and water is automatically injected into balloon d sequentially through port i and path e by the pump. In this case, however, the liquid supply pipe coupled to port i may interfere with the operation of endoscope a, and poses a problem on an improvement of operability.
It is an object of the present invention to solve the above problems.
It is another object of the present invention to provide an ultrasonic endoscope with improved operability.
It is still another object of the present invention to provide an ultrasonic endoscope which can facilitate washing of an observation optical system and water injection into a balloon.